File tree Expand file tree Collapse file tree 5 files changed +149
-0
lines changed
Establishing a Database Connection With SQL in VB.NET
How to Issue a Select and Load the Data Into an Array
How to Issue an Insert to Put Data Into a Database
Setting Up Your Local SQL Server Expand file tree Collapse file tree 5 files changed +149
-0
lines changed Original file line number Diff line number Diff line change 1+ Imports System
2+ Imports System.Data.SQLite
3+
4+ Module Program
5+ Sub Main(args As String ())
6+ Dim connectionString As String = "Data Source=mydatabase.db;Version=3;"
7+ Try
8+ Using conn As New SQLiteConnection(connectionString)
9+ conn.Open()
10+ Console.WriteLine( "Successfully connected to the database!" )
11+ 'You can perform database operations here.
12+ End Using
13+ Catch ex As SQLiteException
14+ Console.WriteLine( "Error: " & ex.Message)
15+ End Try
16+ End Sub
17+ End Module
Original file line number Diff line number Diff line change 1+ Imports System.Data.SQLite
2+
3+ Module Program
4+
5+ Private Const DatabaseFileName As String = "mydatabase.db"
6+
7+ Sub Main(args As String ())
8+ LoadDataIntoArray()
9+ End Sub
10+
11+ Sub LoadDataIntoArray()
12+ ' Set the connection string
13+ Dim connectionString As String = $"Data Source={DatabaseFileName};Version=3;"
14+
15+ ' Set up the SQL query
16+ Dim query As String = "SELECT Name FROM Users"
17+
18+ ' Create a list to store names retrieved from the database
19+ Dim names As New List( Of String )()
20+
21+ Using conn As New SQLiteConnection(connectionString)
22+ conn.Open()
23+
24+ Using cmd As New SQLiteCommand(query, conn)
25+
26+ Using reader As SQLiteDataReader = cmd.ExecuteReader()
27+
28+ ' Add all the names from the database to the list
29+ While reader.Read()
30+ names.Add(reader( "Name" ).ToString())
31+ End While
32+
33+ End Using
34+
35+ End Using
36+ End Using
37+
38+ ' So far the 'names' list has been populated with usernames from the database.
39+ ' You can convert this list to an array if you want:
40+ Dim namesArray() As String = names.ToArray()
41+
42+ ' Print array content for testing purposes
43+ For Each name In namesArray
44+ Console.WriteLine(name)
45+ Next
46+ End Sub
47+
48+ End Module
Original file line number Diff line number Diff line change 1+ Imports System.Data.SQLite
2+
3+ Module Program
4+
5+ Private Const DatabaseFileName As String = "mydatabase.db"
6+
7+ Sub Main(args As String ())
8+ InsertData( "John Doe" , "USA" )
9+ End Sub
10+
11+ Sub InsertData(userName As String , userCountry As String )
12+ ' Set the connection string
13+ Dim connectionString As String = $"Data Source={DatabaseFileName};Version=3;"
14+
15+ ' Set up parameterized SQL query
16+ Dim query As String = "INSERT INTO Users (Name, Country) VALUES (@Name, @Country)"
17+
18+ Using conn As New SQLiteConnection(connectionString)
19+ conn.Open()
20+
21+ Using cmd As New SQLiteCommand(query, conn)
22+ ' Set parameters
23+ cmd.Parameters.AddWithValue( "@Name" , userName)
24+ cmd.Parameters.AddWithValue( "@Country" , userCountry)
25+
26+ ' Run the query
27+ cmd.ExecuteNonQuery()
28+ End Using
29+ End Using
30+
31+ Console.WriteLine( $"User {userName} from {userCountry} added successfully!" )
32+ End Sub
33+
34+ End Module
Original file line number Diff line number Diff line change 1+ Imports System.Data.SQLite
2+
3+ Module DatabaseInitializer
4+
5+ Sub InitializeDb()
6+ ' Designate a new database file named "mydatabase.db"
7+ Dim connectionString As String = "Data Source=mydatabase.db;Version=3;"
8+ Using conn As New SQLiteConnection(connectionString)
9+ conn.Open()
10+
11+ ' Create Users table
12+ Dim createTableQuery As String = "CREATE TABLE IF NOT EXISTS Users (UserID INTEGER PRIMARY KEY, Name TEXT, Country TEXT)"
13+ Using cmd As New SQLiteCommand(createTableQuery, conn)
14+ cmd.ExecuteNonQuery()
15+ End Using
16+
17+ ' Insert initial users
18+ Dim insertUsers As String = "INSERT INTO Users (Name, Country) VALUES (?, ?)"
19+ Using cmd As New SQLiteCommand(insertUsers, conn)
20+ cmd.Parameters.AddWithValue( "Name" , "Alice" )
21+ cmd.Parameters.AddWithValue( "Country" , "USA" )
22+ cmd.ExecuteNonQuery()
23+
24+ cmd.Parameters.Clear()
25+
26+ cmd.Parameters.AddWithValue( "Name" , "Bob" )
27+ cmd.Parameters.AddWithValue( "Country" , "UK" )
28+ cmd.ExecuteNonQuery()
29+
30+ cmd.Parameters.Clear()
31+
32+ cmd.Parameters.AddWithValue( "Name" , "Charlie" )
33+ cmd.Parameters.AddWithValue( "Country" , "Canada" )
34+ cmd.ExecuteNonQuery()
35+
36+ cmd.Parameters.Clear()
37+ End Using
38+
39+ Console.WriteLine( "Database and initial data created successfully!" )
40+ End Using
41+ End Sub
42+
43+ End Module
Original file line number Diff line number Diff line change 1+ Module Program
2+
3+ Sub Main(args As String ())
4+ DatabaseInitializer.InitializeDb()
5+ End Sub
6+
7+ End Module
You can’t perform that action at this time.
0 commit comments